From patchwork Mon Jan 30 04:45:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thiago Jung Bauermann X-Patchwork-Id: 63904 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 3948B3858000 for ; Mon, 30 Jan 2023 04:47:07 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3948B3858000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1675054027; bh=IQ95ekTUCaN+rfTW/X3s2aPzrr9MulFxsjrNtivs69k=; h=To:Cc:Subject:Date:In-Reply-To:References:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=AuVPEy2QpeGNR1spgi1wS55RUEahrnkQSprA9LS2fvgOuDgxiS2Z62DHsupLWE/Xm W7F9Ar2lwlcgitxPXNBhmlJk1eJQ62RNqVIsdvrkXwUMOrhWmrE5kDtJxu0d+Bl2EE yaosuts/X23MVeO6Kf9Rtty1Tgvp0bIqXwaVIL5I= X-Original-To: gdb-patches@sourceware.org Delivered-To: gdb-patches@sourceware.org Received: from mail-oa1-x29.google.com (mail-oa1-x29.google.com [IPv6:2001:4860:4864:20::29]) by sourceware.org (Postfix) with ESMTPS id B625C3858416 for ; Mon, 30 Jan 2023 04:45:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org B625C3858416 Received: by mail-oa1-x29.google.com with SMTP id 586e51a60fabf-163adf0cfc4so2398740fac.7 for ; Sun, 29 Jan 2023 20:45:51 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=IQ95ekTUCaN+rfTW/X3s2aPzrr9MulFxsjrNtivs69k=; b=rhDNmKXGFINqGlRH0Hs3vrvQSebfN3Oxq+EAhW+5IY+kjazoPAZUKT5k6d9PepGomN 6+84Ldn3LPsCB85FGIVuLF6leKuMX5PnrivK74ZQGnY/4hf1XOK7uUryfV97aMiivrC9 42M/xUtIfOUEg39D3msl/E2JjHNRJ1/pqcWBq/QWKzaE6h6/LCNE99qwTvbh0jW6w6oq Z5dU28JCcsoVP7lQIGHChhODW67OfZPSJomhpFh/j9Pg9kxhXhc4jJq96CBembBaIRXJ JWu4PAvPdraTQXULAP5emPwMMXVDoNV4UvX3/p25Y53JNhssnofzXoDTqRxw37glpwLF 9/KQ== X-Gm-Message-State: AO0yUKWjzUdbvYGneS5XI1eaJ85i3VQF1ZHVZq6I4gjQoq+HvFpHJp5I 8fFv92tzGur4hww5+XGCuVzjmt/zJH/LiSYI X-Google-Smtp-Source: AK7set9cKyKekYQ/i78yF+Ur2TuaU2ovY1JQs48pqUnSWqxQt7uyKDNeh8xC/Y0MRYJR38LoVlllMg== X-Received: by 2002:a05:6870:ac1e:b0:163:28c9:beef with SMTP id kw30-20020a056870ac1e00b0016328c9beefmr10486233oab.59.1675053951011; Sun, 29 Jan 2023 20:45:51 -0800 (PST) Received: from localhost ([2804:14d:7e39:8470:df99:10bd:7dca:b2e9]) by smtp.gmail.com with ESMTPSA id pa13-20020a0568701d0d00b0015f9cc16ef7sm4734670oab.46.2023.01.29.20.45.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Jan 2023 20:45:50 -0800 (PST) To: gdb-patches@sourceware.org Cc: Thiago Jung Bauermann , Simon Marchi Subject: [PATCH v3 5/8] gdbserver: Transmit target description ID in thread list and stop reply Date: Mon, 30 Jan 2023 04:45:15 +0000 Message-Id: <20230130044518.3322695-6-thiago.bauermann@linaro.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: <20230130044518.3322695-1-thiago.bauermann@linaro.org> References: <20230130044518.3322695-1-thiago.bauermann@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-11.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Thiago Jung Bauermann via Gdb-patches From: Thiago Jung Bauermann Reply-To: Thiago Jung Bauermann Errors-To: gdb-patches-bounces+patchwork=sourceware.org@sourceware.org Sender: "Gdb-patches" Now that an inferior thread can have a different target description than its process, there needs to be a way to communicate this target description to GDB. So add the concept of a target description ID to the remote protocol, which is used to reference them and allows them to be transferred only once over the wire. The ID is an unsigned integer, and is sent in the 'T AA n1:r1;n2:r2;...' stop reply packet as a new 'n:r' pair, where n is "tdesc" and "r" is an unsigned integer containing the ID. It is also sent in the threads list XML in the response of a qXfer:threads:read request. The ID is sent as a new "tdesc" attribute of the node. To request the target description XML of a given ID, GDB sends the qXfer:features:read request with "target-id-%u.xml" as the annex, where %u is the target description ID. Suggested-By: Simon Marchi Reviewed-by: Luis Machado --- gdb/doc/gdb.texinfo | 27 ++++++++++++++++--- gdbserver/remote-utils.cc | 57 +++++++++++++++++++++++++++++++++++++++ gdbserver/remote-utils.h | 9 +++++++ gdbserver/server.cc | 17 ++++++++++-- gdbserver/server.h | 4 +++ 5 files changed, 109 insertions(+), 5 deletions(-) diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 9c0018ea5c14..fbf7e59853b5 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -42030,6 +42030,10 @@ the stopped thread, as specified in @ref{thread-id syntax}. If @var{n} is @samp{core}, then @var{r} is the hexadecimal number of the core on which the stop event was detected. +@item +If @var{n} is @samp{tdesc}, then @var{r} is the hexadecimal number of +the target description ID (@pxref{Target Description ID}). + @item If @var{n} is a recognized @dfn{stop reason}, it describes a more specific event that stopped the target. The currently defined stop @@ -46546,7 +46550,7 @@ the following structure: @smallexample - + ... description ... @@ -46556,8 +46560,10 @@ Each @samp{thread} element must have the @samp{id} attribute that identifies the thread (@pxref{thread-id syntax}). The @samp{core} attribute, if present, specifies which processor core the thread was last executing on. The @samp{name} attribute, if -present, specifies the human-readable name of the thread. The content -of the of @samp{thread} element is interpreted as human-readable +present, specifies the human-readable name of the thread. The +@samp{tdesc} attribute, if present, specifies the target description +ID of the thread (@pxref{Target Description ID}). The content of +the @samp{thread} element is interpreted as human-readable auxiliary information. The @samp{handle} attribute, if present, is a hex encoded representation of the thread handle. @@ -46767,6 +46773,8 @@ descriptions are accurate, and that @value{GDBN} understands them. target descriptions. @xref{Expat}. @menu +* Target Description ID:: Referencing different descriptions in the + remote protocol. * Retrieving Descriptions:: How descriptions are fetched from a target. * Target Description Format:: The contents of a target description. * Predefined Target Types:: Standard types available for target @@ -46775,6 +46783,14 @@ target descriptions. @xref{Expat}. * Standard Target Features:: Features @value{GDBN} knows about. @end menu +@node Target Description ID +@section Target Description ID + +In cases where a remote target supports threads having different +target descriptions than their parent process, the remote protocol +assigns a non-negative integer to each target description to reference +it in the communication between the host and the target. + @node Retrieving Descriptions @section Retrieving Descriptions @@ -46787,6 +46803,11 @@ qXfer}). The @var{annex} in the @samp{qXfer} packet will be XML document, of the form described in @ref{Target Description Format}. +If target description IDs are being used (@pxref{Target Description ID}), +@value{GDBN} can retrieve a target description with a given ID by using +@samp{target-id-ID.xml} as the @var{annex}, where @var{ID} is the +non-negative integer identifier of the desired target description. + Alternatively, you can specify a file to read for the target description. If a file is set, the target will not be queried. The commands to specify a file are: diff --git a/gdbserver/remote-utils.cc b/gdbserver/remote-utils.cc index 80310bc2c709..baff899307cc 100644 --- a/gdbserver/remote-utils.cc +++ b/gdbserver/remote-utils.cc @@ -1049,6 +1049,53 @@ outreg (struct regcache *regcache, int regno, char *buf) return buf; } +/* See remote-utils.h. */ + +unsigned int +get_tdesc_rsp_id (const target_desc *tdesc) +{ + client_state &cs = get_client_state (); + unsigned int i; + + for (i = 0; i < cs.tdescs.size (); i++) + if (cs.tdescs[i] == tdesc) + return i; + + cs.tdescs.push_back (tdesc); + + return i; +} + +/* See remote-utils.h. */ + +const target_desc * +get_tdesc_from_rsp_id (unsigned int id) +{ + client_state &cs = get_client_state (); + + if (id >= cs.tdescs.size ()) + return nullptr; + + return cs.tdescs[id]; +} + +/* Return the ID as used in the remote protocol for the target descriptor of the + given PTID. */ + +static unsigned int +get_tdesc_rsp_id (ptid_t ptid) +{ + const thread_info *thread = find_thread_ptid (ptid); + const target_desc *tdesc; + + if (thread == nullptr) + tdesc = find_process_pid (ptid.pid ())->tdesc; + else + tdesc = get_thread_target_desc (thread); + + return get_tdesc_rsp_id (tdesc); +} + void prepare_resume_reply (char *buf, ptid_t ptid, const target_waitstatus &status) { @@ -1241,6 +1288,16 @@ prepare_resume_reply (char *buf, ptid_t ptid, const target_waitstatus &status) buf += strlen (buf); current_process ()->dlls_changed = false; } + + if (current_thread->tdesc != nullptr + && current_thread->tdesc != current_process ()->tdesc) + { + sprintf (buf, "tdesc:"); + buf += strlen (buf); + sprintf (buf, "%x", get_tdesc_rsp_id (ptid)); + strcat (buf, ";"); + buf += strlen (buf); + } } break; case TARGET_WAITKIND_EXITED: diff --git a/gdbserver/remote-utils.h b/gdbserver/remote-utils.h index cb2d6c346c99..61ef80b4dad7 100644 --- a/gdbserver/remote-utils.h +++ b/gdbserver/remote-utils.h @@ -75,4 +75,13 @@ int relocate_instruction (CORE_ADDR *to, CORE_ADDR oldloc); void monitor_output (const char *msg); +/* Return the ID as used in the remote protocol for the given target + descriptor. */ + +unsigned int get_tdesc_rsp_id (const target_desc *tdesc); + +/* Return the target description corresponding to the remote protocol ID. */ + +const target_desc *get_tdesc_from_rsp_id (unsigned int id); + #endif /* GDBSERVER_REMOTE_UTILS_H */ diff --git a/gdbserver/server.cc b/gdbserver/server.cc index 21fb51a45d16..2d1062f98468 100644 --- a/gdbserver/server.cc +++ b/gdbserver/server.cc @@ -976,7 +976,15 @@ handle_general_set (char *own_buf) static const char * get_features_xml (const char *annex) { - const struct target_desc *desc = current_target_desc (); + const struct target_desc *desc; + unsigned int id; + + if (strcmp (annex, "target.xml") == 0) + desc = current_target_desc (); + else if (sscanf (annex, "target-id-%u.xml", &id) == 1) + desc = get_tdesc_from_rsp_id (id); + else + desc = nullptr; /* `desc->xmltarget' defines what to return when looking for the "target.xml" file. Its contents can either be verbatim XML code @@ -986,7 +994,7 @@ get_features_xml (const char *annex) This variable is set up from the auto-generated init_registers_... routine for the current target. */ - if (strcmp (annex, "target.xml") == 0) + if (desc != nullptr) { const char *ret = tdesc_get_features_xml (desc); @@ -1664,6 +1672,11 @@ handle_qxfer_threads_worker (thread_info *thread, struct buffer *buffer) if (name != NULL) buffer_xml_printf (buffer, " name=\"%s\"", name); + if (thread->tdesc != nullptr + && thread->tdesc != get_thread_process (thread)->tdesc) + buffer_xml_printf (buffer, " tdesc=\"%u\"", + get_tdesc_rsp_id (thread->tdesc)); + if (handle_status) { char *handle_s = (char *) alloca (handle_len * 2 + 1); diff --git a/gdbserver/server.h b/gdbserver/server.h index 7997d1a32e6e..58be5027795b 100644 --- a/gdbserver/server.h +++ b/gdbserver/server.h @@ -193,6 +193,10 @@ struct client_state /* If true, memory tagging features are supported. */ bool memory_tagging_feature = false; + /* The target descriptions that have been communicated to the client. The + index of a target description in this vector is the ID used to reference it + in the remote protocol. */ + std::vector tdescs; }; client_state &get_client_state ();